Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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BACKGROUND OF T~E INVENTION
Field of the Invention
This invention relates to apparatus for stacking
flat articles, which are preferably provided with locating
holes and preferably consist of bags, which have been
severed from a tubular or semitubular plastic film web and
have been closed by welding and are preferably received
from a wicketer having pairs of transfer arms, which
rotate about an axis, which apparatus comprises a stacking
line comprising endless tensile elements, which are
trained around reversing wheels or reversing rollers and
- are intermittently driven and provided with upstanding
stacking pins or stacking needles, which are secured to
carrying plates~
Description of the Prior Art
_
Apparatus of that kind is disclosed in German
Patent 31 38 221. In the operation of that known
apparatus, double bags which have been severed from a
tubular film web and have been provided hith a seam weld
are deposited on stacking plates, which are carried by
endless chains and are provided on opposite sides of their
longitudinal center line with a series of stacking pins
for retaining the bags. The bags are separed from each
other by means of a heated knife, which is adapted to be
raised and lowered and cuts through the stacks in the
cutting station between the rows of stacking pins.
3û Because the stacking plates also constitute the abutments
for cooperation with the heated knives, said stacking
plates must be relatively large and heavy.
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The present invention provides apparatus whlch ls of
the kind described first hereinbefore and ls readily adaptable to
different bag sizes and changing conditions and permi-ts the
stacks to be acted upon in different ways in a simple manner.
~ ccording to the present invention there is provided an
apparatus for stacking flat articles, which apparatus comprises a
stacking line comprising endless tensile elements, which are
trained around reversing wheels or reversing rollers and are
intermittently driven and provided with upstanding stacking pins
or stacking needles, which are secured to carrying plates, two
stacking lines being provided and different tools for acting on
the intermlttently conveyed stacks being selectively provided and
detachably secured to the frame of the apparatus.
~ hus, in accordance with the invention two stacking
lines are provided and different tools for acting on the inter-
mittently conveyed stacks are selectively provided and detachably
secured to the frame of the apparatus.
secause two stacking lines are provided, processing
tools may be selectively provided between said stacking l~nes and
secured to the frame of the apparatus and may cooperate in any
desired manner because it is no longer necessary to use the
intermittently moving stacking plate as a backing tool. For this
reason the stacking lines may be lighter in weight because they
are required only for stacking and rather than also as backlng
tools.
The tools may comprise an abutment, whlch is secured to
the frame and provided adjacent to the plane of conveyance and is
equal in length to the stacks in their direction of travel, and a
heated cutting knife, which ls adapted to be raised and lowered
and has the same length as the abutment. In that embodlment,
double bags stacked on the stacking lines can be centrally
divided in such a manner than the heated cutting knife will
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simultaneously join the bags of each of the separa-ted s-tacks at
their cut edges. The cutting knife and the abutment may be
replaced as required and may be entirely removed.
Also within the scope of the invention the -tools may
comprise an abu-tment plate, which is fixed to the frame, and
punching or retaining punches and/or perforating knives, which
are adapted to be lowered onto said abutment plate. The provi-
sion of such abutment plate and of retaining punches preferably
associated with that plate
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affords the advantage that the abutment plate may be
formed with apertures so that processing tools may be
provided also below the abutment plate and may be moved
through the apertures in order to act on the stacks. For
instance, a heated cutting knife for dividing the stack
may be moved through the abutment plate from below.
The tensile elements of each stacking line
preferably consist of cogged belts and may be provided
each with a single needle or a single pin so that the
half-stacks into which each stack has been divided by the
longi~udinal cut and which laterally hang down from the
stacking lines will perform an angular movement if the
needle or pin is offset from the center of the stack.
Such an angular movement may be desirable in order to move
the cut edges away from the heated cutting knife.
In another embodiment within the scope of the
invention the longitudinal beams of the two stacking lines
are mounted on a horizontal transverse axle for rotation
therewith about its axis and their intermediate or forward
portions are supported by rams or the like on a beam which
connects the end frame to the wicketer frame and which is
rigidly connected to the end frame and has a forward end
that is mounted on and displaceable along a transverse
axle of the wicketer frame. In that embodiment the end
frame is supported in sliding contact with or by means of
wheels on transversely extending tracks~ which are secured
to the floor so that the end frame is displaceable along
said tracks, and means for moving the end frame in the
transverse direction are provided. For an adaptation to
different bag sizes, the two stacking lines are moved in
mutually opposite directions. For an operation of the
wicketer to form stacks only on one side, the two stacking
lines are transversely moved in unison to such an extent
that the transfer arms on one side of the wicketer are
disposed between the stacking lines. For an operation of
the apparatus for stacking only on one side the set of
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tools need not be removed because they will not interfere with
-the stacking operation.
In a further embodiment within the scope of the lnven-
tion the longitudinal beams of the stacking lines are non~rotat-
ably connected to low-friction bushings, which are slidably
mounted on the transverse axle of the end frame, both longltudi-
nal beams are provided with nuts havlng oppositely handed threads
in threaded engagement with a transversely extending, common
screw, which is rotatable to ad~ust the spacing of the stacking
line, and the longitudinal beams of the stacklng lines are sup-
ported by a low-friction plate, which is carried by the ram or
the like. In that embodiment the spacing of the stacking lines
may be changed in a simple manner by an operation of the screw
for an adaption to different bag sizes.
Two illustrative embodiments of the invention will now
be explained more in detail with reference to the accompanying
drawing, in which:-
Figure 1 is a side elevation showing the stacking appa-
ratus;
Figure 2 is a top plan view showing the stacking appa-
ratus of Figure 1;
Figure 3 is a transverse sectional view taken on lineIII-III in Figure 1 and showing the stacking apparatus provided
with a cutting knife and an abutment which is fixed to the frame;
and
Figure ~ is a sectional view showing the stacking appa-
ratus of Figure 1 ad~acent to the processing tools and a differ-
ent set of tools.
A wicketer frame 3 comprises side members 1,2, in which
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a sha~t 4 is rotatably mounted, whlch ls operable by drlve means,
not shown, and carrier pairs of trans:Eer
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arms 5, which are provided with vacuum cups or gripping
means. The wicketer frame 3 is preceded by a transverse
severing and welding apparatus, which is not shown and
serves to sever bags from a tubular or semitubular plastic
film web and to close the resulting bags by welding~ The
welded bags or double bags are taken from said severing
and welding apparatus by the rotating transfer arms 5,
which thread the bags or double bags on the stacking pins
6, 7 of the stacking lines 8, 9. As soon a stack
consisting of a predetermined number of bags or double
bags has been formed on a set of stacking pins the cogged
belts which carry the stacking pins are advanced over such
a distance that a set of new stacking pins or needles
assume a position for receiving the bags from the transfer
arms.
The side members 11, 12 of the end frame 10 are
interconnected by a forward crossbeam 13. A longitudinal
beam 14 is rigidly connected to the crossbeam 13 and is
provided at its forward end with a bushing 15, which is
slidably mounted on the transverse axle 16 of the wicketer
frame. That transverse axle consists of a tube or steel
round and is connected by brackets 17, 18 to the side
members 1, 2 of the wicketer frame 3.
Adjacent to each of its side members 11, 12, the
end frame 10 is provided with two rollers 19, which are
guided in transversely extending tracks, which are secured
to the floorO The rear portions of the side members 11,
12 of the end frame 10 are also stiffened by a crossbeam
20, which carries on its underside a transversely extending
rack 21, which meshes with a pinion 22 of a gearmotor 23,
which i secured to the floor. The gearmotor 23 is operable
to move the end frame on the rollers 19 in the transverse
direction so that the longitudinal beam 14 is carried along
and the bushing 15 provided at the forward end of the
longitudinal beam 14 performs a corresponding sliding
movement on the transverse axle 16 of the wicketer frame 3.
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Adjacent to the end frame 10 the longitudinal
beams 24 of the two stacking lines 8, 9 are fixed to
transversely extending bushings 25, which are preferably
spherical and are guided on a transverse axle, which
consists of a tube 26 or the like and is held in the side
members 11, 12. In the forward one-third of its length,
the longitudinal beam 24 of each stack-ing line 8 or 9 is
supported on a low-friction plate 28, which is carried by
a ram 29, which is secured to the longitudinal beam 14.
The longitudinal beam 24 of each stacking line 8 or 9 has
a bifurcated forward end portion having legs 3û, in which
the reversing wheels 31 are freely rotatably mounted. The
rear end portion of each beam 24 is also bifurcated to
form legs 32, in which the reversing wheels 33 are
rotatably mounted. The wheels 33 are connected to drive
means. T~he longitudinal beam 24 of each stacking line is
provided with a nut 34. Both nuts 34 are in threaded
engagement with a transversely extending, common screw 35,
which is provided with oppositely handed screw threads
associated with respective ones of the nuts 34 and is
rotatably mounted in the side members 11, 12 of the end
frame. One end portion of the screw 35 extends through
the side member 12 and is provided with a handwheel 36,
which is operable to adjust the spacing of the stacking
lines 8, 9. ~uring an adjustment of that spacing, the
freely protruding beams 24 of the two stacking lines slide
on the plate 28, which is provided with a low-friction
covering.
The lower longitudinal beam connects the
wicketer frame 3 to the end frame 14 and is provided with
lateral base frame members 41, 42, which are connected to
the longitudinal beam 14 by flanges 40. The base frame
members 41, 42 carry side members 43, 44, which are
disposed laterally of the stacking lines 8, 9 and serve to
carry tools for processing the stacks.
In the embodiment shown in Figures l to 3, an
abutment 45 is screw-connected to the lower longitudinal
beam 14 and is provided at its bottom with flanges 46, 47,
which receive the connecting screws, The abutment 45 is
cushioned at its top by a sufficiently heat-resistant
plastic bar 48, the top of which is disposed adjacent to
the plane of travel of the stacking pins 50, which are
carried by plates ~9. The plates 49 which carry the
stacking pins 50 are connected in alternation to revolving
parallel cogged belts 51, 52, which are provided in pairs.
rhe heated cutting knife 53 is mounted on the
side members 43, 44 and is adapted to be raised and
lowered to sever the stacks between the stacking pins 50.
The illustrative embodiment shown in Figure 4
comprises an abutment plate 55, which is fixed to the
frame and has a central aperture 56. Retaining rams 57
and perforating knives 58 are mounted on the side members
43, 44 and disposed above the abutment plate 55 and
adapted to be lowered. A heatable cutting knife 59 is
disposed under the abutment plate and adapted to be raised
and lowered and to extend through the aperture. When the
retaining rams 57 have been lowered, the lower knife 59
can be raised to cut through a stack which lies on the
abutment plate 5û.
In the embodiment shown in Figure 4, needles 61
are secured to the plates 60, which are secured to the
cogged belts. Said needles 61 will pierce the bags
transferred by the transfer arms 5 without a need for a
previous formation of locating holes in such bags.
If each plate 60 is provided with only one
needle 61, which is eccentrically disposed, the stack
section held by each of said needles will pe1form an
angular movement when the stack has been cut through by
means of the heated cutting knife 59. Ry that angular
movement the welded edges of the bags will be moved away
from the cutting knife 59.
